In recent times it has become more and more popular to offer fresh food, salads, fruit, vegetables, chicken, but also cooked and prepared food, healthy food etc. from what often is called a salad bar, where the customer can pick and compose a meal from a number of different products kept in canteens or pans. However, since the food products may remain for some time in the pans, which may be accessed by quite a large number of persons, the requirements as to an appropriate and hygienic storing capability are high. The food products also have to be kept under such conditions, and at such a temperature, that bacterial growth is prevented and the products can be kept fresh, appetizing and are not ruined or deteriorated in any way due to the storing.
To be able to maintain an accurate temperature, e.g. above 0° (to avoid that the products be frozen), but below 8° C., or within more strictly specified temperature limits, several different arrangements have been proposed.
Some known arrangements use cooling elements below the canteens, but it is difficult to obtain an even temperature distribution in the food stored in the pans, independently of the location of the food and of the pans in the arrangement. Covering arrangements used to cover and protect the pans with content are frequently opened by customers accessing the food, each time during a shorter or a longer time period, which makes it even more difficult to obtain and maintain an even temperature distribution throughout the food bar.
Known arrangements therefor also use fan blowers for blowing cold air onto the products e.g. from above, or from below or sideways onto the pans. This is however not an entirely satisfactory solution for several reasons. First, it is not satisfactory from a hygienic point of view, bearing in mind that several individuals serve themselves from the pans which means that air contaminated with bacteria etc. may be blown onto the food. Also other particles, e.g. dust, may be blown onto the food. Second, due to the air flow, the food products may be dried out, and ruined, at least from an aesthetical point of view, and the products will not look fresh, which may reduce the willingness of customers to buy and consume the products. Some products may even loose taste and undergo unwanted changes.
These factors contribute in shortening the time period the products can be kept in the pans, and they may have to be disposed of, even if they actually could have been stored for a longer time period, if stored under appropriate conditions.
Third, it is a waste of energy to have fan blowers active all the time and it is difficult to keep an even temperature distribution.
An uneven temperature distribution may also contribute to the production of harmful microorganisms.
When covering arrangements or lids are opened to provide access to the food products, air of a higher temperature will enter the pans, which means that even more cooling is required. If fans are used, the products will then be even more exposed to cool air, and the drying effect will be further increased, which means that the time period that the products can be stored in the food bar will be even shorter. In addition thereto, when the covering arrangements are opened, this will contribute to an even more uneven temperature distribution.
The more often the food bar is accessed, i.e. the more often the cover is opened, the more difficult it will be to maintain an even temperature distribution, and the losses in cooling power will be further increased. In known arrangements the transfer of cooling power from a cooling arrangement may be as low as 30% or even less, the losses thus being considerable. There may also be a considerable spread in the cooling capacity in different parts of a cooling arrangement, or a cooling element, located close to products in e.g. a food bar, which results in it being extremely difficult to control the temperature in food bar pans or similar holding the products, particularly if the allowed or desirable temperature interval within which the temperature may vary is small.
Still further, the whole chain involved in delivering food, loading the canteens or pans, replacing food products, storing food products in the meanwhile, when pans are likely to soon being emptied, the different shelf times of different products, the varying consumption of different products, all are factors that involve a certain problematic as far as intermediate storing, replacement, refilling of pans etc. are concerned.
Today products have to be fetched from a refrigerating facility located distant from the food bar, which means that it is difficult to serve the customers in an optimal manner and timing is difficult if one or more pans are run out of content. It is time consuming as well as laborious for staff to all the time keep up to date information concerning the content, e.g. the filling degree in the pans, and to, at the appropriate moment in time, fetch products from an intermediate storage, involving carrying the pans or the products around in the store, which also may affect the temperature of the products, and the hygienic standard.